Summary: In a 3-month analysis of the MOBILE trial in adults with type 2 diabetes on basal insulin, continuous glucose monitoring lowered HbA1c more than fingerstick monitoring, improved time in range, and reduced hypoglycaemia, with benefits appearing within the first week.
PICO Summary
| Element | Detail |
|---|---|
| Population | 175 adults with type 2 diabetes on basal insulin without prandial insulin; randomised 2:1, 3-month analysis of the MOBILE RCT, USA (industry-funded). |
| Intervention | Real-time continuous glucose monitoring (n=116). |
| Comparison | Standard blood glucose (fingerstick) monitoring (n=59). |
| Outcome | HbA1c fell from 9.1% to 8.0% with CGM versus 9.0% to 8.5% with fingerstick (adjusted difference -0.6%; p<0.001). Time in range rose more with CGM (+9.3%; p<0.001), time above 250 mg/dL fell more (-5.8%; p<0.001) without increasing time below 70 mg/dL, and weekly hypoglycaemic events were fewer. CGM metrics improved within the first 7 days. |
CGM vs fingerstick in basal-insulin type 2 diabetes
RCT · type 2 diabetes · 3 months
In basal-insulin-treated type 2 diabetes, CGM lowered HbA1c by 0.6% more than fingerstick monitoring over 3 months, with more time in range and no increase in hypoglycaemia.
Expert Commentary
This is a clinically useful analysis because it extends continuous glucose monitoring’s value into a large and often overlooked group, patients with type 2 diabetes on basal insulin alone, where the technology is sometimes assumed to matter less than in intensively insulin-treated disease. The result is both statistically and clinically meaningful: a 0.6% HbA1c advantage over fingerstick monitoring, achieved through more time in range and less marked hyperglycaemia, and importantly without any increase in time below range, so glucose improved through better-informed behaviour and titration rather than by simply driving glucose down at the cost of lows. The speed of effect, with metrics improving in the first week, is a nice demonstration of how real-time feedback changes day-to-day decisions. My main caveat is interpretive rather than methodological: the trial was industry-funded and open by nature, since monitoring method cannot be blinded, and this is a three-month window from a study population that opted into technology. Can I use this with my patients? Yes, readily. It supports offering CGM to basal-insulin-treated type 2 patients who are above target, both to lower HbA1c and to reduce hypoglycaemia, while I remain attentive to cost, access, and the minority who find sensors uncomfortable.
References
Martens TW, Beck RW, Griffen C, et al. Rapid improvements in glycemic management with use of continuous glucose monitoring in adults with type 2 diabetes treated with basal insulin: 3-month analysis of the MOBILE study. BMJ Open Diabetes Res Care. 2025;13(6):e005469. doi:10.1136/bmjdrc-2025-005469